path: root/comm/mailnews/mime/src/mimetext.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 * This Original Code has been modified by IBM Corporation. Modifications made
 * by IBM described herein are Copyright (c) International Business Machines
 * Corporation, 2000. Modifications to Mozilla code or documentation identified
 * per MPL Section 3.3
 *
 * Date             Modified by     Description of modification
 * 04/20/2000       IBM Corp.      OS/2 VisualAge build.
 */
#include "mimetext.h"
#include "mimebuf.h"
#include "mimethtm.h"
#include "comi18n.h"
#include "mimemoz2.h"

#include "prlog.h"
#include "prmem.h"
#include "plstr.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsIPrefLocalizedString.h"
#include "nsMsgUtils.h"
#include "nsMimeTypes.h"
#include "nsServiceManagerUtils.h"

#define MIME_SUPERCLASS mimeLeafClass
MimeDefClass(MimeInlineText, MimeInlineTextClass, mimeInlineTextClass,
             &MIME_SUPERCLASS);

static int MimeInlineText_initialize(MimeObject*);
static void MimeInlineText_finalize(MimeObject*);
static int MimeInlineText_rot13_line(MimeObject*, char* line, int32_t length);
static int MimeInlineText_parse_eof(MimeObject* obj, bool abort_p);
static int MimeInlineText_parse_end(MimeObject*, bool);
static int MimeInlineText_parse_decoded_buffer(const char*, int32_t,
                                               MimeObject*);
static int MimeInlineText_rotate_convert_and_parse_line(char*, int32_t,
                                                        MimeObject*);
static int MimeInlineText_open_dam(char* line, int32_t length, MimeObject* obj);
static int MimeInlineText_initializeCharset(MimeObject* obj);

static int MimeInlineTextClassInitialize(MimeInlineTextClass* clazz) {
  MimeObjectClass* oclass = (MimeObjectClass*)clazz;
  MimeLeafClass* lclass = (MimeLeafClass*)clazz;
  PR_ASSERT(!oclass->class_initialized);
  oclass->initialize = MimeInlineText_initialize;
  oclass->finalize = MimeInlineText_finalize;
  oclass->parse_eof = MimeInlineText_parse_eof;
  oclass->parse_end = MimeInlineText_parse_end;
  clazz->rot13_line = MimeInlineText_rot13_line;
  clazz->initialize_charset = MimeInlineText_initializeCharset;
  lclass->parse_decoded_buffer = MimeInlineText_parse_decoded_buffer;
  return 0;
}

static int MimeInlineText_initialize(MimeObject* obj) {
  // This is an abstract class; it shouldn't be directly instantiated.
  PR_ASSERT(obj->clazz != (MimeObjectClass*)&mimeInlineTextClass);

  ((MimeInlineText*)obj)->initializeCharset = false;
  ((MimeInlineText*)obj)->needUpdateMsgWinCharset = false;
  return ((MimeObjectClass*)&MIME_SUPERCLASS)->initialize(obj);
}

static int MimeInlineText_initializeCharset(MimeObject* obj) {
  MimeInlineText* text = (MimeInlineText*)obj;

  text->inputAutodetect = false;
  text->charsetOverridable = false;

  // Figure out an appropriate charset for this object.
  if (!text->charset && obj->headers) {
    if (obj->options && obj->options->override_charset) {
      if (obj->options->default_charset) {
        text->charset = strdup(obj->options->default_charset);
      } else {
        text->charsetOverridable = true;
        text->inputAutodetect = true;
        text->needUpdateMsgWinCharset = true;
        text->charset = strdup("");
      }
    } else {
      char* ct =
          MimeHeaders_get(obj->headers, HEADER_CONTENT_TYPE, false, false);
      if (ct) {
        text->charset = MimeHeaders_get_parameter(ct, "charset", NULL, NULL);
        PR_Free(ct);
      }

      if (!text->charset) {
        // If we didn't find "Content-Type: ...; charset=XX", then look
        // for "X-Sun-Charset: XX" instead. (Maybe this should be done
        // in MimeSunAttachmentClass, but it's harder there than here.)
        text->charset =
            MimeHeaders_get(obj->headers, HEADER_X_SUN_CHARSET, false, false);
      }

      // iMIP entities without an explicit charset parameter default to
      // US-ASCII (RFC 2447, section 2.4). However, Microsoft Outlook generates
      // UTF-8 but omits the charset parameter.
      // When no charset is defined by the container (e.g. iMIP), iCalendar
      // files default to UTF-8 (RFC 2445, section 4.1.4).
      if (!text->charset && obj->content_type &&
          !PL_strcasecmp(obj->content_type, TEXT_CALENDAR))
        text->charset = strdup("UTF-8");

      if (!text->charset) {
        text->charsetOverridable = true;
        text->inputAutodetect = true;
        text->needUpdateMsgWinCharset = true;

        if (obj->options && obj->options->default_charset)
          text->charset = strdup(obj->options->default_charset);
        else
          text->charset = strdup("UTF-8");
      }
    }
  }

  if (text->inputAutodetect) {
    // We need to prepare lineDam for charset detection.
    text->lineDamBuffer = (char*)PR_Malloc(DAM_MAX_BUFFER_SIZE);
    text->lineDamPtrs = (char**)PR_Malloc(DAM_MAX_LINES * sizeof(char*));
    text->curDamOffset = 0;
    text->lastLineInDam = 0;
    if (!text->lineDamBuffer || !text->lineDamPtrs) {
      text->inputAutodetect = false;
      PR_FREEIF(text->lineDamBuffer);
      PR_FREEIF(text->lineDamPtrs);
    }
  }

  text->initializeCharset = true;

  return 0;
}

static void MimeInlineText_finalize(MimeObject* obj) {
  MimeInlineText* text = (MimeInlineText*)obj;

  obj->clazz->parse_eof(obj, false);
  obj->clazz->parse_end(obj, false);

  PR_FREEIF(text->charset);

  // Should have been freed by parse_eof, but just in case...
  PR_ASSERT(!text->cbuffer);
  PR_FREEIF(text->cbuffer);

  if (text->inputAutodetect) {
    PR_FREEIF(text->lineDamBuffer);
    PR_FREEIF(text->lineDamPtrs);
    text->inputAutodetect = false;
  }

  ((MimeObjectClass*)&MIME_SUPERCLASS)->finalize(obj);
}

static int MimeInlineText_parse_eof(MimeObject* obj, bool abort_p) {
  int status;

  if (obj->closed_p) return 0;
  NS_ASSERTION(!obj->parsed_p, "obj already parsed");

  MimeInlineText* text = (MimeInlineText*)obj;

  // Flush any buffered data from the MimeLeaf's decoder.
  status = ((MimeLeafClass*)&MIME_SUPERCLASS)->close_decoder(obj);
  if (status < 0) return status;

  // If there is still data in the ibuffer, that means that the last
  // line of this part didn't end in a newline; so push it out anyway
  // (this means that the parse_line method will be called with a string
  // with no trailing newline, which isn't the usual case). We do this
  // here, rather than in MimeObject_parse_eof, because MimeObject isn't
  // aware of the rotating-and-converting / charset detection we need to
  // do first.
  if (!abort_p && obj->ibuffer_fp > 0) {
    status = MimeInlineText_rotate_convert_and_parse_line(obj->ibuffer,
                                                          obj->ibuffer_fp, obj);
    obj->ibuffer_fp = 0;
    if (status < 0) {
      // We haven't found charset yet? Do it before return.
      if (text->inputAutodetect)
        status = MimeInlineText_open_dam(nullptr, 0, obj);

      obj->closed_p = true;
      return status;
    }
  }

  // We haven't found charset yet? Now is the time.
  if (text->inputAutodetect) status = MimeInlineText_open_dam(nullptr, 0, obj);

  return ((MimeObjectClass*)&MIME_SUPERCLASS)->parse_eof(obj, abort_p);
}

static int MimeInlineText_parse_end(MimeObject* obj, bool abort_p) {
  MimeInlineText* text = (MimeInlineText*)obj;

  if (obj->parsed_p) {
    PR_ASSERT(obj->closed_p);
    return 0;
  }

  // We won't be needing this buffer any more; nuke it.
  PR_FREEIF(text->cbuffer);
  text->cbuffer_size = 0;

  return ((MimeObjectClass*)&MIME_SUPERCLASS)->parse_end(obj, abort_p);
}

// This maps A-M to N-Z and N-Z to A-M. All other characters are left alone.
// (Comments in GNUS imply that for Japanese, one should rotate by 47?)
static const unsigned char MimeInlineText_rot13_table[256] = {
    0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   10,  11,  12,  13,  14,
    15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,
    30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,
    45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,
    60,  61,  62,  63,  64,  78,  79,  80,  81,  82,  83,  84,  85,  86,  87,
    88,  89,  90,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,
    77,  91,  92,  93,  94,  95,  96,  110, 111, 112, 113, 114, 115, 116, 117,
    118, 119, 120, 121, 122, 97,  98,  99,  100, 101, 102, 103, 104, 105, 106,
    107, 108, 109, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,
    135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149,
    150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164,
    165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179,
    180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194,
    195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209,
    210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224,
    225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239,
    240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254,
    255};

static int MimeInlineText_rot13_line(MimeObject* obj, char* line,
                                     int32_t length) {
  unsigned char *s, *end;
  PR_ASSERT(line);
  if (!line) return -1;
  s = (unsigned char*)line;
  end = s + length;
  while (s < end) {
    *s = MimeInlineText_rot13_table[*s];
    s++;
  }
  return 0;
}

static int MimeInlineText_parse_decoded_buffer(const char* buf, int32_t size,
                                               MimeObject* obj) {
  PR_ASSERT(!obj->closed_p);
  if (obj->closed_p) return -1;

  // MimeLeaf takes care of this.
  PR_ASSERT(obj->output_p && obj->options && obj->options->output_fn);
  if (!obj->options) return -1;

  // If we're supposed to write this object, but aren't supposed to convert
  // it to HTML, simply pass it through unaltered.
  if (!obj->options->write_html_p &&
      obj->options->format_out != nsMimeOutput::nsMimeMessageAttach)
    return MimeObject_write(obj, buf, size, true);

  // This is just like the parse_decoded_buffer method we inherit from the
  // MimeLeaf class, except that we line-buffer to our own wrapper on the
  // `parse_line` method instead of calling the `parse_line` method directly.
  return mime_LineBuffer(buf, size, &obj->ibuffer, &obj->ibuffer_size,
                         &obj->ibuffer_fp, true,
                         ((int (*)(char*, int32_t, void*))
                          /* This cast is to turn void into MimeObject */
                          MimeInlineText_rotate_convert_and_parse_line),
                         obj);
}

#define MimeInlineText_grow_cbuffer(text, desired_size)                       \
  (((desired_size) >= (text)->cbuffer_size)                                   \
       ? mime_GrowBuffer((desired_size), sizeof(char), 100, &(text)->cbuffer, \
                         &(text)->cbuffer_size)                               \
       : 0)

static int MimeInlineText_convert_and_parse_line(char* line, int32_t length,
                                                 MimeObject* obj) {
  int status;
  nsAutoCString converted;

  MimeInlineText* text = (MimeInlineText*)obj;

  // In case of charset autodetection, charset can be overridden by meta
  // charset.
  if (text->charsetOverridable) {
    if (mime_typep(obj, (MimeObjectClass*)&mimeInlineTextHTMLClass)) {
      MimeInlineTextHTML* textHTML = (MimeInlineTextHTML*)obj;
      if (textHTML->charset && *textHTML->charset &&
          strcmp(textHTML->charset, text->charset)) {
        // If meta tag specified charset is different from our detected result,
        // use meta charset, but we don't want to redo previous lines.
        PR_FREEIF(text->charset);
        text->charset = strdup(textHTML->charset);

        // Update MsgWindow charset if we are instructed to do so.
        if (text->needUpdateMsgWinCharset && *text->charset)
          SetMailCharacterSetToMsgWindow(obj, text->charset);
      }
    }
  }

  status = obj->options->charset_conversion_fn(
      line, length, text->charset, converted, obj->options->stream_closure);

  if (status == 0) {
    line = (char*)converted.get();
    length = converted.Length();
  }

  // Now that the line has been converted, call the subclass's parse_line
  // method with the decoded data.
  status = obj->clazz->parse_line(line, length, obj);

  return status;
}

// In this function call, all buffered lines in lineDam will be sent to charset
// detector and a charset will be used to parse all those line and following
// lines in this mime obj.
static int MimeInlineText_open_dam(char* line, int32_t length,
                                   MimeObject* obj) {
  MimeInlineText* text = (MimeInlineText*)obj;
  nsAutoCString detectedCharset;
  nsresult res = NS_OK;
  int status = 0;
  int32_t i;

  if (text->curDamOffset <= 0) {
    // There is nothing in dam, use current line for detection.
    if (length > 0) {
      res = MIME_detect_charset(line, length, detectedCharset);
    }
  } else {
    // We have stuff in dam, use the one.
    res = MIME_detect_charset(text->lineDamBuffer, text->curDamOffset,
                              detectedCharset);
  }

  // Set the charset for this object.
  if (NS_SUCCEEDED(res) && !detectedCharset.IsEmpty()) {
    PR_FREEIF(text->charset);
    text->charset = ToNewCString(detectedCharset);

    // Update MsgWindow charset if we are instructed to do so.
    if (text->needUpdateMsgWinCharset && text->charset)
      SetMailCharacterSetToMsgWindow(obj, text->charset);
  }

  // Process dam and line using the charset.
  if (text->curDamOffset) {
    for (i = 0; i < text->lastLineInDam - 1; i++) {
      status = MimeInlineText_convert_and_parse_line(
          text->lineDamPtrs[i], text->lineDamPtrs[i + 1] - text->lineDamPtrs[i],
          obj);
    }
    status = MimeInlineText_convert_and_parse_line(
        text->lineDamPtrs[i],
        text->lineDamBuffer + text->curDamOffset - text->lineDamPtrs[i], obj);
  }

  if (length) status = MimeInlineText_convert_and_parse_line(line, length, obj);

  PR_Free(text->lineDamPtrs);
  PR_Free(text->lineDamBuffer);
  text->lineDamPtrs = nullptr;
  text->lineDamBuffer = nullptr;
  text->inputAutodetect = false;

  return status;
}

static int MimeInlineText_rotate_convert_and_parse_line(char* line,
                                                        int32_t length,
                                                        MimeObject* obj) {
  int status = 0;
  MimeInlineTextClass* textc = (MimeInlineTextClass*)obj->clazz;

  PR_ASSERT(!obj->closed_p);
  if (obj->closed_p) return -1;

  // Rotate the line, if desired (this happens on the raw data, before any
  // charset conversion).
  if (obj->options && obj->options->rot13_p) {
    status = textc->rot13_line(obj, line, length);
    if (status < 0) return status;
  }

  // Now convert to the canonical charset, if desired.
  bool doConvert = true;
  // Don't convert vCard data
  if (((obj->content_type) &&
       (!PL_strcasecmp(obj->content_type, TEXT_VCARD))) ||
      (obj->options->format_out == nsMimeOutput::nsMimeMessageSaveAs) ||
      obj->options->format_out == nsMimeOutput::nsMimeMessageAttach)
    doConvert = false;

  // Only convert if the user prefs is false.
  if ((obj->options && obj->options->charset_conversion_fn) &&
      (!obj->options->force_user_charset) && (doConvert)) {
    MimeInlineText* text = (MimeInlineText*)obj;

    if (!text->initializeCharset) {
      MimeInlineText_initializeCharset(obj);
      // Update MsgWindow charset if we are instructed to do so.
      if (text->needUpdateMsgWinCharset && *text->charset)
        SetMailCharacterSetToMsgWindow(obj, text->charset);
    }

    // If autodetect is on, push line to dam.
    if (text->inputAutodetect) {
      // See if we reach the lineDam buffer limit, if so, there is no need to
      // keep buffering.
      if (text->lastLineInDam >= DAM_MAX_LINES ||
          DAM_MAX_BUFFER_SIZE - text->curDamOffset <= length) {
        // We let open dam process this line as well as thing that already in
        // Dam. In case there is nothing in dam because this line is too big, we
        // need to perform autodetect on this line.
        status = MimeInlineText_open_dam(line, length, obj);
      } else {
        // Buffering current line.
        text->lineDamPtrs[text->lastLineInDam] =
            text->lineDamBuffer + text->curDamOffset;
        memcpy(text->lineDamPtrs[text->lastLineInDam], line, length);
        text->lastLineInDam++;
        text->curDamOffset += length;
      }
    } else
      status = MimeInlineText_convert_and_parse_line(line, length, obj);
  } else
    status = obj->clazz->parse_line(line, length, obj);

  return status;
}